Synthetic compost for mushroom



Reissued Oct. 13, 1942 UNITED STATES: PATENT OFFICE 22,202 I SYNTHETIC COMPOST FOR MUSHROOM CULTURE Benjamin B. Stoller, Coatcsville, Pa, assimor to Louis F. Lambert, Coatesville, Pa'. I,

No Drawing. Original No. 2,260,201, dated October 21, 1941, Serial No. 278,076, June 8, 1939. Application for reissue January 17', 1942, Serial 9 Claims. (01. 71-3) in this automobile age, numerous attempts have been made to find substitutes. According to applicant's knowledge, none of these prior attempts have been successful.

Detailed reviews of previous attempts to prepare synthetic composts, have been published recently by E.- B. Lambert (Botanical Review 4:397-426. July 1938) and J. W. Sinden (Pa. Agr. Exp. Station Bulletin #365. ,June 1938). In a review of 166 publications on mushroom culture, E. B. Lambert concludes that None of the experimental station workers recommends the adoption of artificial manure alone by commercial growers except on an experimental scale," and that as a rule synthetic composts will yield only A to A as much per square foot as beds of horse manure composts. The reason for this has not been satisfactorily worked out and cons'titutes an intriguing problem No best formula can be given at this time. After a review of previous studies on synthetic composts by other investigators, Sinden concludes that in no case have the composts reported by these investigators beenvery satisfactory. All require a long composting period and the yields are so variable as to make their commercial use inadvlsable.

- While laboratory studies published on the factors affecting mycelial growth have been informative, they have provided no measure, or method, or formulation of the conditions and requirements for the economical production of sporophores (the fruiting body or mushroom). Formulae and methods remained to be established.

Then again, the requirements of themycelium are so simple, especially on autoclaved media, that facts obtained by measuring mycelial growth are often misleading frcm the'point of view oi sporophore production.

In a great deal of the literature, especially patent literature, there are claims for satisfactory mo adding to the fibrous material about 14 lbs. of

' lial wth myce gro synthetic composts because a good mycelium growth 'was obtained, whereas actually a good spawn growth does not presume a good production of sporophores. In this connection E. B.

Lambert, in the reference above cited, statesthat There is little known regarding the special nutrient requirements for the development -of mushroom sporophores. That such requirements exist seems probable from the fact that beds of artiflcialcomposts supporting an excellent -run of spawn frequently produce only a comparatively few mushrooms. The same material when mixed half and half with composted horse manuremay yield normally. Aside from the few papers already cited in connection with the suppl'ementing of manure, this whole problem remained to be investigated."

The method, in accordance-with my invention, comprises the determination what nutrient salts and nitrogenous materials are required, their ratio and their formulation for commercial sporophore production, the factors that affect composting, and the method used to aid, supplement and, almost, if not entirely, eliminate the microbial decomposition of the materials employed. While these formulae and methods have been developed primarily for sporophore production, they may be used also for,spawn (mushroom manufacture, after certain modifications have been made which will be described. Though good sporophore production presumes good spawn growth, the contrary does not hold.

' After numerous experiments, it has been found that a ton of synthetic compost with a fibrous material containing water (or containing about 700 lbs.,of dry matter), may be made by varied as follows; and are herein called total quantities limits Pounds N- 12 to 20 P205 3 t0 6 9 "to 1B potassium oxide) ratio should be kept at about mushroom mycelium,

4-1-3, although it allows for some variation, but not beyond the total quantity limits set forth. These total quantity limits are set for 500 to 700 lbs. of the dry fibrous material which is used as the basic substrate. The average N-P-K content of this fibrous material is included in the total quantity limits, and the variation specified in the total quantity limits allows for the variation in the availability of the N-P-K constituents of the fibrous materials. The additional tities are determined. Its nitrogen difiiciencies, if any, are then corrected by adding a nitrogenous material. It may now have a shortageof P205 or K20; if it does, then sources of these fractions are now added. The number of nitrogenous, phosphoric acid and potash sources used are immaterial, as long as they add up to the total sources of N-P-K that may be required to be added to the fibrous material to attain the desired ratio and total quantity limits, may cause the total dry matter to be increased to 6.00 to 900 lbs., depending on how rich or poor these sources are in N-P-K, but the finished compost will average about 700 lbs. dry matter so that at 65% moisture, will be equal to one ton. The exact quantity to be used, depends on the sub-division and absorptive properties of the fibrous materials employed, those that are more finely subdivided and more absorptive will allow larger quantities of N-P-K to be used. Some variation, of course, is naturally inherent for any par- .ticular species or variety of the mushroom.

The quantity of lime to add depends on the acidity of the finished compost. It isdesirable toobtain a pH of 7.0 to 8.0 in the finished compost. Ordinarilythis will require 5 to lbs.

' of hydrated lime (Ca(OH)z). Magnesium lime may also be used, but it is preferable to have about 50% in it present as calcium lime.

The elements, Mn, Fe, Cr, Al, Cu, Zn, B, Br,

and I, the salts and compounds of which shall hereafter be referred to as the "minor elements, give further ments with some fibrous materials have given significant increases in yield of mushrooms. The cations and anions with which these elements are combined are unimportant from the point of view of their nutritive and catalytic functions. However, when the elements Mn, Fe, Al, Cr, Cu, and Zn are also required to function as precipitants of nitrogenous substances and of carbonates, it is preferable to use their soluble salts, the anions,

chloride and sulfate having been found satisfactory.

If the fibrous materials contain 50 to 100 lbs. lignin, it is not necessary to add lignin, but depend on the microbial decomposition to liberate the lignin from the fibrous material. The lignin is necessary to precipitate or adsorb the nitrogenous material so. that it will be difllcult, if not impossible, for most microorganisms, except the to hydrolze or be able to utilize the nitrogenous material. As will be shown later, lignin set free by chemical agents. or isolated lignin, may be used directly on the nitrogenous material and so greatly reduce, if not eliminate, the lengthy microbial decomposition; and also be more certain that the lignin has been set free to combine with the nitrogenous material. As will be shown later, also many other substances besides lignin may be used. In fact,

, post, is to analyze the materials to be employed into their chemical constituents. First of all the fibrous material is considered. If it has suiflcient lignin or similar material, then its N-P-K quanincreases in yield. These minor elequantities and ratio desired.

An example of this computation is as follows: if it is desired to prepare a ton of synthetic compost entirely by microbial decomposition, with wheat straw as the fibrous material, and dry brewers grains asthe source of N, then since the straw contains sufficient ligning, its N-P-K content is considered and found that in 500 lbs. it has 2.5-0.74.0 lbs. respectively. Then, 250 lbs. of dry brewers grains, which contain 10 /2 lbs. of N and 2.6 lbs. of P205, are added. The 2 /2 lbs. N of the straw and the 10 lbs. N of the grain are equal to 13 lbs.,. so the N is satisfied. Since the P205 adds up to only 3.1 lbs. 7 /2 lbs. of superphosphate' (20% P205) are added and that adds up to 4.8 lbs. P205, which is satisfactory in this case: 12 lbs. of sulfate of potash (50% K20) are now added, which with the 4 lbs, in the straw, is equal to 10 lbs. By adding the minor elements (2 lbs. M11804, 1 1b. F6504, 4 oz. A12(SO4) a, 4 oz. FJuSO-r, 2 oz. ZnSO4, 1 oz. Cr2(SO4.)a 2 oz. HaBOa, it oz. KBr, ,6 oz..KI) and adding 9 lbs. lime to bring the pH at 7.0 to 8.0, the formulation is completed. The tabulation of this compost is as follows:

Any fibrous material may be used, such as straw or stover, but fibrous materials which will not decay or undergo extensive microbial decomposition are preferable. Substances which are impregnated or contain large quantities of lignin, or tannin, as in many roots, bark, nuts, and wood, or industrial by-products such as spent licorice roots, and spent myrobalan nuts, spent bark and leaves (material from which tannin has been extracted for industrial use) are especially suitable.

Any nitrogen source may be used. Sources of nitrogen which have been found satisfactory are brewers grains, malt sprouts, fungal tissue of the fermentation industry such as yeast and aspergillus, coca shell and cake from which the theobromine has been extracted, soybean meal, dried blood, tannery sludge, urea, ammonium compounds; calcium cyanamide, and calcium and potassium nitrates.

Any source of potassium and phosphorous compounds may be used. Potassium compounds that have been found satisfactoryare the fertilizer grades of potassium chloride and sulfate. Ash

of" various plant materials may also be used, such as yeast ash, molasses ash, cotton seed hull ash. Also, any source of phosphorous may be used, although superphosphate is the source most avail able. Commercial sodium hexametaphosphate is not only valuable as a source of P205, but for other purposes as will be shown later. If the potassium or phosphorous materials are insoluble, they may be treated with acids and alkali to ognized the function of the alkali elements as potassium, sodium, and ammonium has not been duly accredited. The function of these alkali in the solution and dispersion of the lignin after the more easilydecomposable carbonaceous matter has disappeared, has been overlooked. The inability to obtain black synthetic composts, like manure composts, was because no potash or soda,

or an insignificant quantity of these were added.

The potassium salts may be'also effective by supplying the microorganisms with an essential element, so that they can utilize the carbonaceous materials more rapidly, and so free the lignin.

While the alkaline salts of potassium and sodium, such as potassium or sodium carbonates are more rapidly eflective than their neutral salts such as their chlorides and sulfates, they require considerable precautions in their use, because they are extremely toxic to myceiial growth. The alkaline salts, however are. especially useful when the fibrous materials to be used in preparing'composts contain a large percentage of ceiiulose. If, after the potash or soda has dispersed the lignin, the precaution is taken to add the minor elements, as already stated, or in fact any chemical compound which will give an insoluble carbonate, or a strong acid which will destroy the carbonate, and so, at the same time, convert the sodium or potassium carbonate to their neutral salts, these substances will be an effective aid in the microbiological decomposition of the plant material. However, potassium chloride and sulfate have been found highly satisfactory in most cases.

Another method to be used in composting is to allow fibrous materials, which have been adjusted to 65% moisture. to undergo a long period of storage so that the lignins are eventually liberated even with the small quantities of N-P-K which may be present. or the required quantities of P20: and K20 are added, or sodium carbonate I and potassium carbonate may be added with the precaution already stated, but less than of the required nitrogen is added,- and this long storage microbial decomposition is allowed to take place. Of course, the lignin containing materials may be soaked in a solution of about 5 per cent sodium and potassium carbonates to liberate the llnin; but this method is'described below. When the fibrous material has become dark brown or black,

indicating lignin liberation, a nitrogenous material high in proteins,-such as yeast cells or dried blood, and also nitrates, are now added; the desired ratio and the other factors required as already described for the formulation of composts, is now brought to completion. These composts require no further composting but are placedinthemushroombedsandallowedto undergo the thermophilic fermentation as is practiced in the sweating" stage. This method is more satisfactory with some fibrous materials istactorymethodthanwaitingfornflcmorgancarbonaceous materials with which they are associated, is to extract or free these lignins and tannins by physical and chemical agencies. Lignin may be obtained, as an industrial by-product or extracted from such carbonaceous materials 7 they exist in a free state and to prepare the composts directly from the extracted material and extracts together. The carbohydrates that may be converted to sugars in the course of these extractions, may be changed to aldehydes, which are also satisfactory as shown below. Thus, chemical agents, in contradistinction to microbiological agents, are used to bring about the free existence of lignins and tannins for the fixation of nitrogenous materials in .the preparation of synthetic composts.

The lignins and tannins are combined with the nitrogenous materials into acomplex material which is difficult to hydrolyze and be utilized by most microorganisms at the temperature at which the mushroom mycelium is grown. It has also been observed that the mushroom mycelium will grow more rapidly on nitrogenous materials which have been treated with lignin or tannin than untreated material-even under sterile conditions. In fact, urea which is so toxic to the mushroom mycelium in concentration over of the dry substrate even under sterile conditions, is satisfactory when properly treated with tannin or lignin. Ammonium compounds may likewise be made non-toxicby treatment with these substances. Instead of describing the am- I monium compounds as treated with lignin, this method may be stated as the ammoniation of the lignin. Many other substances besides lignin and tannin will combine by precipitation, coagulation or adsorption with nitrogenous substances. Sulfate .and chlorides of Cr, Al, and Fe made increasingly basic or heated so that they undergo the process of oliiication, may be used. Many compleir substances formed by oiiiication, condensacals. These substances may also be satisfactory for the purpose of making composts even if they are not separated from their source of manufac- 'ture. For example, when carbonaceous materials "are treated with mineral acids to prepare furfura'ldehyde, it is not'necessary to separate the latter. Or if nitric acid is allowed to act upon certain proteins, resins or aromatic compounds it is not necessary to separate the picric acid formed. Thus 'it is shown that if a chemical substance, which is not in itself similar in the precipitation and adsorption properties like ligismstoliberatelignimandtanninsfromthenninortannimbutcausesthefreeexistenceof brewers grains, soybean /2 and the K reduced to 1%;

,trations of the numerous binations possible by the methods described in' ess whereby chemical agents will precipitate-or adsorb nitrogenous substances so that these substances are not easily decomposable or hydrolyzable by most microorganisms, but is especially suitable for the growth or the mushroom mycelium. Or, the process may be defined as the treatment of nitrogenous materials by certain chemical agents, such as lIgmn tannin, picrlc acid, sodium hexametaphosphate, furiuraldehyde, basic chrome gone olification, and phenolsuli'onic and naphthalene-sulfonic acids which have undergonev condensation so that the nitrogenous substances are more readily and rapidly available to the mushroom mycelium than other biological organisms. This process shall, hereafter be referred to as coprination, and the agents which bring it about as coprinating agen Specifically, a coprinating agent may be defined as a complex chemical compound which is generally characterized by having polyhydroxy groups, exists in a state of, or has a tendency to undergo olification, condensation and polymerization, and precipitates or adsorbsnitrogenous substances. The nitrogenous substances suitable for coprination are the proteins, amino acids, urea, ammonium, and cyanamide compounds and substances that contain a high percentage of proteins, such as meal, dried blood, and yeast cells. This combination by precipitation or adsorbtion causes the nitrogenous substances to become difilcult to hydrolyze or to utilize by most micro-organisms or enzymesat the temperature used for the growth of the mushroom mycelium, but serves as an excellent substrate for the growth of the mushroom mycelium.

The formulations, composting methods and coprination process may also be used for the manufacture of spawn (the mycelium grown on a substrate to be used to inoculate bedsi'rom which'sporophore production is to be obtained). However the total quantities of N-P-K may be sharply reduced; the and P reduced to to used in sporophore' production. Itis also preferable to use higher concentrations of lime and of the minor elements, as indicated in my Patent No; 2,189,303 dated Feb. 6, 1940.

The following examples serve only as illus:

formulations and comthis application.

Where minor elements are referred-to, in'the following examples, the quantities are understood to be those given in the early part of this speciilcation. I

Example #1 Material '1??? N no. xjo

Lbs. Lbs. Lb. Lb: Spent licorice roots (67.5% moisture).-- 2,000 6. 5 l. Dried brewers grains 200 8. 2 2.0 Superphosphate (m% P205) 1.0 a l Potassium chloride (50% K) 22 11.0

The brewers grains, superphosphate, and potassium chloride are thoroughly mixed with the sulfate which has underto A 01 the quantities is concerned roots and allowed obtained when the lime was Potassium chloride (50% K10).

to undergo a microbial decomposition. The compost heap is turned two or three times over a period of, for example, 15 to 25 days. A grower skilled in the art knows when the composting is completed. The compost is then filled in beds and allowed to undergo the thermophilic fermentation (at to F.) known as the sweating stage." The beds are then cooled and inoculated as is well known.

Example #2 Material my The procedure is the same for Example #1, except that lime is added, preferably at the last turning. Good results, however, have also been diluted with soil and added along with the other materials.

Example #3 Spent licorice roots (67.5% moisture) Dried brewers grains Urea Superphosphate (20% P105).... Potassium sulfate (50% K10) Dry Quebraeho tannin extract .1 Hydrated limo The procedure is. the same as for Example #2. The tannin is, preferably, sprayed on the compost heap during the second turning.

' Example #4 Material" 9 no. KiO

i ,Lm. Lbs. Lba. Lbs. Spent licorice roots (67.5% moisture). 2,000 6. 5 1.0 Ammo-phos (iii-m) l5 2. 5 3.0 Calcium cynnamide (17% N). 20 4. 0 Potassium sulfate (m% K:()) 20 l0. 0 Potassium chloride (50% K10) 3 i. 5

The procedure is the same as for Example #1.

Example #5 Quan- Material m N P10; K,0

Spent Myrobalan nuts (65% moisture) Dried blood Dried brewers grains The procedure is the same as Example #2,

except that the nuts are, preferably, ground up to the size of wheat grains or thereabouts. The lime and minor elements may be mixed at the start, or sprayed on at the final turning.

Erample #6 Material. N no. mo

Wheat straw (dry) Dried d u cap 0 a Pomum sulfate (56% m0) Potassium chloride (60% K 0) Minor Hydrated lime...

The straw may be all long, or one-half chopped, or all chopped. The straw may be better wetted by spraying with a "wetting" agent such as Aersol, Dupontol, Aresket," sodium hexametaphosphate, and numerous other commercial wetting agents. Or the straw may be' dipped in a tank of water containing a wetting agent.

' Alter the straw has taken up about 50% water,

it is then mixed with thevarious materials as shown in Example #6. About four turnings over a period, for example, of to days are required to compose the straw, butif the straw is all chopped, less time will be required. The hydrated lime and minor elements are, preferably, added at the last turning. If sodium hexametaphosphate is used in place of superphosphate only 3% lbs. will be required, since it contains 68% The roots are allowed to lay in storage several months. After most of the cellulose has disappeared, the roots are'thoroughly mixe with a solution or calcium nitrate and the other materials as shown. Without any further composting the roots are placed in the beds and allowed to gothrough the sweating stage.

Compos'ts in Examples #8 to 11 inclusive are prepared with coprinatins agents. These exam-- ples illustrate the employment of four diflerent kinds of nitr s us materials with two coprinat- 'ing agents. The coprinating agent is dissolved in suillcient water (preferably hot water) to compietely immerse the nitrogenous material to be used. its pH is adjusted at 4.0 to 8.0, but preferably on the acid-side; .and the nitrogenous material is allowed to soak in it from a fewminutes to several days. After suflicient soaking, salts and minor elements and lime are added so that the pH is, preferably, at about 6.5. The solution is then thoroughly mixed with a fibrous material;

and heated with hot air at 140 F. or allowed to undergo the aerobic thermophilic fermentation of the sweating" stage. After cooling, the beds are inoculated with spawn as usual.

The coprinating agents may be used in various combinations, and also successions of coprinations may be practiced with difierent coprinating agents. Various combinations of lignin, tannin, chrome, aldehydes, for example, may be used. Or first, one agent as furfuraldehyde or naphthalene sulfonic acid in condensation product may be used, followed by in or tannin. The variations of this process of coprination are countless. The aim here is only to describe the process of coprination itself, and illustrate it with a few examples, some of which have resulted the highest yields ever recorded.

Example #8 usu- Material N no. mo

. Lbs. 156;. Lbs. Lbs. Spent licorice roots mo1sture)..... 1, 300 6. 5 1.0 Extracted yeast 90 8.0 2.0 Suge'phosphate (20% Pros) 5 1.0 As from alcohol manufacture (30% K1 35 10.5 Dry Quebraeho tannin extrac 35 Minor elements The tannin is dissolved in about gallons of hot water. The pH of this solution is about 5.0.

The yeast is then mixed into the solution. Good results have been obtained both by letting the yeast soak several hours, or over a day, in hot as well as cold solution. the superphosphate, potash, minor elements, and lime, if necessary. are added, thoroughly mixed with the yeast-tannin solution and then mixed with the roots to take up all free moisture.

The pH of the solution and the amount of water used should be regulated so that the moisture of the finished compost is about to and the pH about 7.0 to 8.0. The compost is now placed in the mushroom growing beds and heated with hot air at 140 F., or allowed to undergo the thermophilic fermentation of the "sweating" stage, which lasts 3 to 7 days. The thermophilic organisms which can grow'in the presence of the coprinating agents are not detri-' mental to the ensuing mushroom mycelial growth, but rather aid in the final adjustment of the moisture and pH of the compost. After cooling the beds are inoculated with spawn as usual.

Example #9.

Material ff N no. mo

Spent licorice roots (50% moisture).... 1,300 6.5 1.0 ft D brewers grains 200 8.2 2.0 Su hosphate(m% P) 5 1.0

K030m alcohol manufacture (30% eoaua'flaaui'saaaai::::::::::::: so :33: :::::1 .fff Minor elements The procedure is the same as for Example #8 except that the pH of the llgnin salt is reduced to about 6.0 with sulfuric or hydrochloric acid.

, the compost so prepared is then placed in beds 7 A longer soaking ,oi the grains is preferable.

After sufllcient soaking Uramon (urea wit Example #10 Quan- Mate ial My Spent licorice roqts (50% moisture)...

h 42% 1 Superphospliate (20% F101;)... Ash irom alcohol manufacture (30% K10) 35 l0. 5 Dry Quebracho tannin e rtract 40 I 14. 9 4. 10.

The procedure is samefas for Example #8.

Example #11 Quan- Matenal my N P205 K Lbs. Lbs. Lbs. Lba. Spent licorice/roots (50% mo1sture). l, 300 6.5 1.0 Dried blood 60 8.0 0. 5 Superphosphate (%Pz0s) l5 3. 0 Ash from alcohol manufacture (30% K10) r 35 10. 5 Calcium lignosulfonate 50 Minor elements 14.5 4. s 10. 5

The procedure is same as for Example #9.

Summary The formulations, methods and examples, herein set forth are believed to be a complete disclosure of how to prepare synthetic composts for the commercial production of sporophores. While some of the materials and chemicals used herein have been mentioned in other attempts to produce synthetic composts, yet, in contrast to the formulations and. methods of reducing these materials and chemicals to uniform composts which will give consistently high yields,

other attempts employed them indiscriminately,

insufficiently and incompletely, so that incon-' sistent yields, always less than produced by horse manure composts were obtained. In the most recent publication on the preparation of synthetic composts (Sinden, reference above) urea is selected as a source of nitrogen in preference to such compounds as ammonium phosphate, or potassium nitrate, because it leaves no inorganic residue which" might interfere with thedecomposition process or of the mushroom development later-,-thus, entirely disregarding the necessity for regulation of the phos phorus and potassium. This investigator (Sinden) further states that excepjt for the pH we a have yet to find achemical relation between the substances present in the finished compost commercial production of sporophores. This large quantity of potassium salts is required both for the dispersion of the copri'nating agents and for the development of the sporophores, which are high in potassium. v Although the minor elements have been mentioned, more or less in connection with mycelial growth, no method of formula has ever attempted to employ them for the production of sporophores. In their application in the methods herein described, they have been used as precipitants of nitrogenous substance and carbonates and for their nutritive and catalytic functions.

Not only have the factors afiecting composting been described but methods toregulate it have been developed. By storing fibrous materials containing 65% moisture, or by using chemical and physical agents, so that the lignin of the methods described herein, the yields have manure composts yield 1 to 2 lbs. of mushwhich can be regarded as essential to the growth of the mushrooms. Some other investigators, however, have referred to the N-P-K relationship indirectly, but supplied insufficient orexcessive quantities, so that their yields havebeen inconsistent and poor. A method and formula on how to control the N-P-K ratio and total quantities for the commercial production of sporophores had not been developed. The methods and formulae described herein are not merely designed for just growing spawn or mushrooms, but for the commercial production of sporophores, and that means: obtaining higher yields than obtained with horse manure composts, While very small quantities of potash are required for mycelial growth, large quantities as shown in these formulations are required for the 7 5 been figured as pounds of mushrooms (stubs cut oif) picked per square foot of bed surface. While 10% to 35% more bed surface may be obtained with synthetic composts than with manure composts from the same quantity of dry weight of materials, still, the greater cost for materials and the skilled labor required to produce synthetic composts, may to a certain extent or under certain conditions, counterbalance this gain of bed .surface. In other words, the cost of production of synthetic composts, in accordance with this invention, may be greater than for manure composts (depending, of course, on the .-price of manure), even after reckoning on the increased bed surface obtained with the former and it is only by developing a method which will give a greater yield of mushrooms, that synthetic composts become a practical reality. Whereas rooms per square foot, the synthetic composts prepared by the method in accordance with this invention, yield from 2 lbs. to as high as 4 lbs.

per sq. ft, of bed surface.

What-I claim is:

1. In the method of making and using synthetic composts formushroom culture, the steps which consist in mixing fibrous material and source materials containing N, PzOm and K20 in the proportlons relatively as follows:-12 to 20 lbs. N, .3 to 6 lbs. P205, 9 to 16 lbs. K20 and one ton of fibrous material having a moisture content of 65% to"%, composting, then placing in mushroom beds, sweating, cooling and inoculating with mushroom spawn.

l 2. In the method ofv making and using a synthetic compost formushroom culture the steps which consist in adding source materials containing N,.PzQs, and K20 to fibrous material, having a moisture content of 65% to 75%, so that a- 3. In the method of making and using a syn thetic compost for mushroom culture, the steps which consist in adding, source materials containing N, P205 and K20 to fibrous material having a moisture content of 65% to 75% so that a mixture will be produced in the proportions relatively as follows: 12 to 20 lbs. N, 3 to 6 lbs. P205, 9 to 16.lbs. K20, and one ton of said fibrous material, after allowing for the presence of these constituents in th'e fibrous materials, adding 2 lbs. manganese sulphate, 1 lb. ferrous sulphate, 4 oz. aluminum sulphate, 4 oz. copper sulphate, 2 oz. zinc sulphate, 1 oz. chromic sulphate, 2 oz. boric acid, oz. potassium bromide, oz. potas slum iodide, adjusting the pH at 7.0 to 8.0 composting, then placing in mushroom beds, sweat- 7. In the method of making and using a synthetic compost for mushroom culture, the steps which consist in mixing source materials containing N, which has beensoaked for a few minutes to several days, in an acid tannin solution, then adding to this solution source materials containing P205, and K20, and then adding 2 lbs. manganese sulphate, 1 lb. ferrous sulphate, 4 ozs.

aluminum sulphate, 4 ozs. copper sulphate, 2 ozs. zinc sulphate, 1 oz. chromic sulphate, 2oz. boric acid, *5; oz. potassium bromide, y, oz. potassium iodide, adjusting the pH at 6.5 to 7.0 and then ing, cooling and inoculating with mushroom lows, in a ton of fibrous material 12 to lbs. N,

3 to 6 lbs. P205; and 9 to 16 lbs. K20, composting, then placing in mushroom beds, sweating, cooling and inoculating with mushroom spawn.

5. In the method of preparing and using a synthetic compost for mushroom culture, the

steps which consist in adding sources of P205 and K20 to plant materials containing to 1% N, made up to 65% to 75% moisture, allowing a microbial fermentation to take place, so that lignin becomes the predominating organic plant constituent, and then adding sources of nitrogen high in proteins and also nitrates so that the nitrogen content is increased to 2% to 3% N, then placing the product in mushroom beds, sweating, cooling and inoculating with mushroom spawn.,

6. In the method of making and using a synthetic compost for mushroom culture, the steps which consist in mixing fibrous material and source material containing N, K20, and P205, in

the proportions relatively as follows: 12 to 20 lbs. N, 3 to 6 lbs. P205 and 9 to 16 lbs. K20, and 500 to 700 lbs. of air-dry fibrous material and then adding sufficient water so that the entire mass will have a moisture content of 65% to 75%, and said proportions in one ton of compost,

composting, then placing in mushroom beds,

- sweating, cooling and inoculating with mushroom spawn.

'room spawn.

adding to said mixture and thoroughly mixing therewith air-dry fibrous material so that the complete compost will have proportions relatively as follows: 12 to 20 lbs. of N, 3 to 6 lbs. P205, 9 to 16' lbs. K20 and 500-700 lbs. of air-dry fibrous material, and 65% to 75% moisture per ton, and then placing the compost so prepared in mushroom growing beds to undergo the thermophilic fermentation of the sweating stage, and then after cooling, inoculating with mush- 8. In the method of making and using a synthetic compost for mushroom culture, the steps which consist in mixing source materials containing N, which has been soaked for a few minutes to several days, in an acid lignin solution, thenadding to this solution source materials containing P205, and K20, and then adding 2 lbs. manganese sulphate, 1 lb. ferrous sulphate, 4 ozs. aluminum sulphate, 4 ozs. copper sulphate, 2 ozs.

I zinc sulphate, 1 oz. chromic sulphate, 2 ozs. boric acid, 5"; oz. potassium bromide, oz. potassium iodide, adjusting the pH at 6.5 to 7.0 and then adding to said mixture and thoroughly mixing therewith air-dry fibrous material so that the complete compost will have proportions relatively as follows: 12 mm lbs. N, 3 to 6 lbs. P205, 9 to 16 lbs. K20 and 500 to 700 lbs. of air-dry fibrous material and 65% to 75% moisture per ton, and

then placing the compost so prepared in mushroom growing beds to undergo the thermophilic fermentation of the sweating" stage, and then after cooling, inoculating with mushroom spawn.

9. A synthetic compost for mushroom culture, comprising, in approximate proportions relatively as followsz-one ton of fibrous mat ei'ial containing .to moisture and source materials to produce 12 to 20 lbs. N, 3 to 6 lbs. P205 and 9 to 16 lbs. K20, after allowing for the presence of these constituents in thesaid fibrous material; said substances being composted, and then inoculated with mushroom spawn.

' BENJAMIN B. STOLLER. 

